Knob assemblies with encoder controlled illumination

ABSTRACT

A knob assembly includes a repositionable knob having an outer surface and an inner surface defining an interior, light-transmissive indicia provided on the knob and viewable from the outer surface, at least one light source located relative to the repositionable knob and emitting light into the interior of the knob to backlight the light-transmissive indicia, a position sensor providing a position output indicative of the position of the repositionable knob, and a controller configured to receive the position output and control the at least one light source to maintain a predetermined backlighting of the indicia.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/575,438, filed Dec. 18, 2014, now U.S. Pat. No. 9,607,792, which isincorporated herein by reference in its entirety.

BACKGROUND

Household appliances, examples of which may include a clothes washer,clothes dryer, an oven, a cooktop, a refrigerator, or a dishwasher,etc., perform useful cycles of operation and often have electrical andmechanical components responsible for implementing the cycle ofoperation of the appliance, with one or more of the componentscontrolling the operation of the other components. For example, acontroller, such as a microprocessor-based controller, having a printedcircuit board (PCB) with memory, may be used to control the operation ofthe various components to implement a cycle of operation.

A Human Machine Interface (HMI) (a/k/a User Interface) may be providedas part of or separate from the controller to provide input/outputcommunication between a user of the appliance and the controller. One ormore knob assemblies are often part of the HMI to provide a way for thehuman to provide input to the HMI.

SUMMARY

An aspect of the present disclosure relates to a knob assembly includinga repositionable knob having an outer surface and an inner surfacedefining an interior, a structural framework located within theinterior, and a light-transmissive indicia provided on the knob andviewable from the outer surface, at least one light source locatedrelative to the repositionable knob and emitting light to transmit lightinto the interior of the knob past the structural framework andbacklight the light-transmissive indicia, a position sensor providing aposition output indicative of the position of the repositionable knob,and a controller receiving the position output and operably coupled tothe at least one light source to independently control an intensity oflight transmitted by the at least one light source, the controllerprogrammed to use the position output to control the intensity of the atleast one light source to at least partially compensate for any blockedlight to maintain a predetermined backlighting of the light-transmissiveindicia.

A knob assembly including a repositionable knob having an outer surfaceand an inner surface defining an interior and a light-transmissiveindicia provided on the knob and viewable from the outer surface, atleast one light source located relative to the repositionable knob andemitting light to transmit light into the interior of the knob andbacklight the light-transmissive indicia, a position sensor providing aposition output indicative of the position of the repositionable knob,and a controller receiving the position output and operably coupled tothe at least one light source to independently control an intensity oflight transmitted by the at least one light source, the controllerprogrammed to use the position output to control the intensity of the atleast one light source to maintain a predetermined backlighting of thelight-transmissive indicia.

A knob assembly including a repositionable knob having an outer surfaceand an inner surface defining an interior, a structural frameworklocated within the interior, and a light-transmissive indicia providedon the knob and viewable from the outer surface, at least one lightsource located relative to the repositionable knob and emitting lightinto the interior of the knob past the structural framework andbacklight the light-transmissive indicia, a position sensor providing aposition output indicative of the position of the repositionable knob,and a controller receiving the position output and operably coupled tothe at least one light source to independently control an intensity oflight transmitted by the at least one light source based on the receivedposition output to maintain a predetermined backlighting of thelight-transmissive indicia.

BRIEF DESCRIPTION OF THE FIGURES

In the drawings:

FIG. 1 is a side, cross-sectional view of a first embodiment of a knobassembly according to the invention, with the knob assembly comprising aknob and a rotary encoder.

FIG. 2 is a top view of the knob of a second embodiment.

FIG. 3 is a top view of a knob of a third embodiment.

FIG. 4 is a side, cross-sectional view of a fourth embodiment of a knobassembly of the invention.

FIG. 5 is an enlarged view of FIG. 4 of a light source of the fourthembodiment.

DETAILED DESCRIPTION

Referring to FIG. 1, a human user interface 10 is shown and includes acontroller in the form of a PCB 12 with a microprocessor 14, a fascia 16overlying the PCB 12, and a knob assembly 18 carried by the PCB 12 andextending through the fascia 16.

The knob assembly 18 comprises a repositionable knob, illustrated as arotatable knob 20, at least one light source illustrated as multiplelight sources 22 each having a light emitter 60, with correspondinglight guides 24, and a position sensor, which is illustrated as a rotaryencoder 26. The rotatable knob 20 comprises an outer surface 28 and aninner surface 30 defining an interior 32. A light-transmissive indicia36 is provided on the knob 20 and viewable from the outer surface 28. Astructural framework 34 is located within the interior 32 to providestructural support to the knob 20. The structural framework 34 may be ofany desired structure. However, in many implementations, it is a hub 38and spoke 40 structure. The structural framework 34 may also vary inthickness.

The light sources 22 and rotary encoder 26 are mounted to the PCB 12,which, as illustrated, is on a rear side 42, but could just as easily bemounted to a front side 44 of the PCB 12. The light guides 24 extendthrough an opening in the PCB 12 and the fascia 16, and direct the lightemitted by the light source 22 from the rear side 42, through the PCB 12and fascia 16, and into the interior 32 of knob 20. In alternateembodiments, at least some of the light sources 22 may be mounted to afront side 44 of the PCB 12.

The rotary encoder 26 includes an encoder body 50, defining an interior52, and a rotatable shaft 54, mounted to the body 50 for relativerotation. The knob 20 is mounted to the rotatable shaft 54. The shaft 54has one end fixedly mounted to the structural framework 34 and anotherend rotatably mounted to the PCB 12. The knob 20 is typically mounted tothe shaft 54 to prevent relative rotation between the shaft 54 and knob20. The encoder body 50 may be mounted, such as by soldering, to the PCB12.

The encoder body 50 may be operably coupled to the microprocessor 14 viaa conductive trace on the PCB 12. The rotary encoder 26 may beconfigured to transform the rotational position of the shaft 54 intoelectrical signals, which may output to the microprocessor 14 along thetrace. The electrical signals may directly indicate a selection by theuser or may be used by the microprocessor 14 to determine the selectionby the user.

The encoder 26 may be a hollow-shaft rotary encoder or any othersuitable type of encoder. Further, the encoder 26 may be implemented aseither an absolute or a relative rotary encoder. The encoder 26 may haveits own circuit board and processor to determine the rotary position ofthe shaft 54 and/or knob 20. The circuit board of the encoder 26 may beconnected to the microprocessor 14. The rotary encoder 26, PCB 12, lightguide 24, and light source 22 collectively define the major element of arotary encoder assembly.

The knob 20 and shaft 54 may have various shapes and/or designs. By wayof non-limiting examples, the knob 20 and shaft 54 may be a singularpiece or may alternatively be operably coupled together in a suitablemanner. The knob 20 may have an axis about which it rotates and it iscontemplated that regardless of the configuration of the knob 20 andshaft 54, the rotational axis of the knob 20 may be collinear with arotational axis of the shaft 54.

The light transmissive indicia 36 may comprise an insert provided in therotatable knob 20 and may be of different color, material, and/ortransmittance than that of knob 20. The light transmissive indicia 36may comprise multiple light transmissive indicia 36, with thepredetermined backlighting highlights one or all of the multiple lighttransmissive indicia 36. In alternate embodiments, the knob 20 or theindicia 36 may comprise a light diffuser (not shown) to spread out orscatter the light in the interior 32 of knob 20.

The light sources 22 are located relative to the rotatable knob 20 andbelow at least a portion of the structural framework 34 to transmitlight into the interior 32 of the knob 20 past the structural framework34 to backlight the light-transmissive indicia 36. At least some of thelight sources 22 and/or light guides 24 may be mounted directly belowthe interior 32 of knob 20. Light sources 22 may be light emittingdiodes (LEDs) or alternative light emitting devices. The structuralframework may be of a transparent or semi-transparent material to betterallow light to pass through to the indicia 36.

Each light source 22 may be of a single color or multiple colors. Forsingle color, a single color LED is contemplated. For multiple colors, amultiple color LED, like a tri-colored LED, is contemplated. Themicroprocessor 14 may control the mixing of light from each light source22 to create custom color(s) dependent on the rotary position of knob20. The microprocessor 14 may execute a suitable program that isconfigured to select the color based on the rotational position.

A predetermined backlighting may be applied to the light transmissiveindicia 36 based on the rotational position of the knob 20. Themicroprocessor 14 uses the rotational position of the knob 20 todetermine the intensity and/or color of each of the light sources 22 togenerate the predetermined backlighting, which is accomplished by analgorithm being implemented as a computer program being executed by themicroprocessor 14, with the algorithm using the rotational position ofthe knob 20 as input. By predetermined backlighting, it is meant that atleast the intensity of the light, and optionally the color, of the lightsources is controlled so that a predetermined backlight pattern isapplied to the light-transmissive indicia 36. One such predeterminedbacklighting is one that provides the light-transmissive indicia with 36a substantially even backlighting when viewed from the outer surface 28of the knob 20.

While an even distribution of light may seem simple at first, when onerealizes that the structural framework 34 will block one or more of thelight sources 22, an even distribution becomes more complicated becausethe intensity must be varied to compensate for the blocked light sources22. The problem is further exacerbated in that the effected lightsources 22 and the amount of blockage is dependent on the rotationalposition of the knob 20. The invention solves this problem by using therotational position of the knob to determine which light sources 22 areblocked and the degree of blockage of each of the blocked light sources22 and thereby determine the intensity level for each of the lightsources to obtain an even distribution. The microprocessor 14 then usesthis information to control the intensity of the light sources 22.

One method for implementing the invention can be a data table havingcorresponding intensity levels for a plurality of rotational positions.In such a scenario, the microprocessor 14 receives the position outputand operably coupled to the multiple lights sources 22 to independentlycontrol the intensity of light transmitted by the multiple light sources22 according to the intensity values for the corresponding rotationalposition. In such a solution, it is inherent that the data table valuestake into account the position of the structural framework 34 relativeto the corresponding rotational position. These relationships can bedetermined by suitable testing for a given structural framework 34 in aparticular knob 20. A different data table may be provided for differentknobs 20/structural framework 34.

An alternative would be to provide a map of the structural frameworkrelative to the rotational position of the knob. The algorithm couldthen take into account the rotational position from the encoder 26 andthe corresponding location of the structural framework 34 based on themap and use these to determine the intensity of illumination for thelight sources 22 to obtain the even distribution.

The intensity of each light source 22 may be individually controlled toobtain the desired backlighting. In some cases it may be necessary toincrease the intensity of one or more of the light sources 22 whiledecreasing the intensity of the other light sources. For example, when alight source is partially blocked by the structural framework, theintensity of that light source may be increased. If the intensityincrease is not sufficient to obtain the even distribution, for example,the intensity of the light sources may be reduced to obtain an overalleven distribution.

The predetermined backlighting may include other types of backlightingthan an even distribution. Another example of backlighting is one thathighlights the user selection while evenly backlighting the rest of theknob 20. As with the prior example, the data table would have rotationalpositions corresponding to the predetermined user selections and thecorresponding intensity levels for each of the light sources 22. Theintensity levels could be determined by testing and a data tableprovided for a particular knob 20/structural framework 34. Otherpredetermined backlighting scenarios are contemplated.

Referring now to FIG. 2, a second embodiment of a knob assembly 118 isillustrated. Like parts between the second and first embodiments willuse the same numbers with a 100 prefix. The second embodiment knobassembly 118 is similar to the first embodiment, except that thehub/spoke structural framework 134 of the outer surface 128 has a morecomplex shape which can be thought of in terms of the transmissiblenature of the materials. The structural support may be thought of as theleast transmissive or even opaque areas, collectively referred to as lowtransmissive areas 186, whereas the indicia 136 may be thought of as themore transmissible areas. The indicia 136, illustrated as a spiral, andthe multiple light sources 122 are positioned about the shaft 154 in acircular fashion, resulting in the indicia 136 being non-symmetricrelative to the circularly arranged light sources 122. The indicia 136may be unevenly illuminated due to the blockage of the light sources 122by low transmissive areas 186, which may be opaque. As illustrated, somelight sources 122 are covered more than other light sources 122 by thelow transmissive area 186. Each light source 122 is controlledindependently. Based on the rotational position of the knob 120, theintensity of the light from the light sources 122 will be adjusted. Forexample, if a single light source 122 is known to be partially orcompletely blocked by a low transmissive area 186, the intensity oflight source 122 can be increased to better provide a more evenlyilluminated indicia 136. If the increase in intensity of the blockedlight source 122 is insufficient for an even distribution, then theintensity from one or more of the other light sources 122 may bereduced.

FIG. 3 illustrates a third embodiment of a knob assembly 218. The thirdembodiment is similar to the first and second embodiments, with theprimary difference being the third embodiment has an outer surface 228which is primarily made up of multiple, discrete indicia 236 withstructural framework in the form of a hub 238. For the most part, likeparts between the two embodiments will be identified with like numerals,with the numerals of the third embodiment having the 200 prefix. Eachindicia 236 is of a pie-shaped design wherein each pie section isdirectly over one light source 222 for at least one rotational position.It is contemplated that the rotation of the knob assembly 18 is indexedsuch that the knob assembly 18 may be rotated through discreterotational positions. In each of the positions, each of the pie sectionswill overlie a light source 222. To indicate which of the rotationalpositions is “selected” by the user based on the rotation of the knobassembly 18, the selected indicia 236 will be illuminated, eitherbrighter or dimmer, than the other indicia 236, with it being brighterin most cases. To make the selected indicia brighter, the light source222 underlying the indicia 236 may be increased in intensity and/or theother light sources may be decreased in intensity. The selected indicia236 will result in a single, substantially brighter illuminated, area284. This may function to visually display to the user which functionthe knob assembly 18 is selecting.

In the scenario of the third embodiment, knob assembly 218 is likely tobe configured to have discrete stops or detents to provide tactilefeedback to the user of their selection. The corresponding data tablewould include a list of rotational positions and the correspondingintensity levels for each of the light sources 122. The intensity levelswould take into account and compensate for any structural framework,which would likely comprise walls extending radially outwardly from thecenter of the knob 220, along the sides of the pie-shape sectors, aswell as take into account the additional intensity needed for area 284to be substantially brighter.

FIG. 4 illustrates a fourth embodiment of a knob assembly 318. For themost part, like parts between the embodiments will be identified withlike numerals, with the numerals of the prior embodiments having the 300prefix. A human user interface 310 is shown and includes a controller inthe form of a PCB 312 with a microprocessor 314, and a fascia 316overlying the PCB 312. The fourth embodiment is similar to the priorthree embodiments, with the primary difference being the fourthembodiment has side-firing light sources 322, located on a rear side 342of the PCB 312 with corresponding light guides 324, which emit lightinto an interior 332 of the encoder 326. The side-firing light sources322 could just as easily be mounted to a front side 344 of the PCB 312.This side-firing configuration may be used with any of the embodiments.

In the fourth embodiment, the rotatable knob 320 comprises an outersurface 328 and an inner surface 330 defining an interior 332 with astructural framework 334 located within the interior 332, and alight-transmissive indicia 336 provided on the knob 320 and viewablefrom the outer surface 328. Light sources 322 comprise a light emitter360. Light sources 322 may be LEDs or alternate light emitting devices.

The rotary encoder 326 comprises a body 350 defining an interior 352,and a rotatable shaft 354 supported by the body 350. A light guide 374may be provided within the shaft 354 or integrally formed with the shaft354. The rotatable knob 320 is fixedly mounted to the rotatable shaft354 to effect rotation of the knob 320. The body 350 comprises at leastone window 362 corresponding to the at least one light sources 322through which light emitted from the light sources 322 is transmitted tothe interior 352. The body 350 may comprises a peripheral side wall andthe windows 362 may be spaced about the peripheral sidewall. The lightsources 322 correspond to windows 362 and optically couple the bodyinterior 332 to the knob interior 332. Wherein the light emittedexteriorly of the body 350 from one of the light sources 322 passesthrough the corresponding window 362 and is transmitted by thecorresponding light guide 374 from the body interior 352 to the knobinterior 332.

FIG. 5 illustrates an enlarged view of the light source 322 and encoderbody 350 to illustrate the relationship between the light emitted fromthe light source 322 and the windows 362. The light source 322 emits alight having a beam angle 364. The at least one light source 322 and atleast one window 362 are relatively positioned such that an arc segmentdefined by the beam angle 364 passes through the at least one window362, which ensures that the greatest amount of light is provided to theinterior 332 of the encoder 326. The beam angle 364 is the degree ofwidth that light emits from a light source 322. In specific terms thisis the angle between the opposing points on the beam axis where theintensity drops to 50% of its maximum. The beam angle 364 may be largerthan the window 362 if the light source 322 is not immediately outsideof the window 362. In alternate embodiments, the light source 322 may becloser to or enclosed by the encoder body 350 and light emitter 360 maybe located within the window 362 in order to reduce light bleeding awayfrom the encoder 326.

While the window 362 is illustrated as an opening in the encoder body326, the window 362 may be a transmissive portion in the encoder body.As a transmissive portion, it may be either translucent or transparent.The transmissive portion may also be colored to alter the color of theemitted light. It is further contemplated that the window 362 mayessentially be an opening in the body 326 in which a window “pane” isprovided, with the pane providing the transmissive portion, for example.

While various embodiments of the application have been described, itwill be apparent to those of ordinary skill in the art that many moreembodiments and implementations are possible that are within the scopeof this invention. Accordingly, the invention is not to be restrictedexcept in light of the attached claims and their equivalents.

What is claimed is:
 1. A knob assembly, comprising: a repositionableknob having an outer surface and an inner surface defining an interior,a structural framework located within the interior, and alight-transmissive indicia provided on the repositionable and viewablefrom the outer surface; at least one light source located relative tothe repositionable knob and emitting light to transmit light into theinterior of the repositionable knob past the structural framework andbacklight the light-transmissive indicia; a position sensor providing aposition output indicative of a position of the repositionable knob; anda controller receiving the position output and operably coupled to theat least one light source to independently control an intensity of lighttransmitted by the at least one light source, the controller programmedto use the position output to control the intensity of the at least onelight source to at least partially compensate for any blocked light tomaintain a predetermined backlighting of the light-transmissive indicia.2. The knob assembly of claim 1 wherein the predetermined backlightingcomprises a generally even backlighting across the light-transmissiveindicia for intended movements of the repositionable knob.
 3. The knobassembly of claim 1 wherein the light-transmissive indicia comprises aninsert provided in the repositionable knob.
 4. The knob assembly ofclaim 1 wherein the at least one light source comprises a light guide.5. The knob assembly of claim 1 wherein the at least one light sourcecomprises multiple light sources.
 6. The knob assembly of claim 1wherein the repositionable knob comprises a rotatable knob.
 7. The knobassembly of claim 1 wherein the light-transmissive indicia comprisesmultiple light transmissive indicia.
 8. The knob assembly of claim 7wherein the predetermined backlighting highlights one of the multiplelight transmissive indicia.
 9. The knob assembly of claim 8 wherein thepredetermined backlighting substantially illuminates the other of themultiple light transmissive indicia.
 10. The knob assembly of claim 1further comprising a printed circuit board (PCB) to which therepositionable knob and the at least one light source are mounted. 11.The knob assembly of claim 10 wherein the PCB has a front sideconfronting the repositionable knob and a rear side opposite the frontside, and the at least one light source is mounted to one of the frontor rear sides.
 12. The knob assembly of claim 11 wherein the at leastone light source comprises a light emitter and a light guide directingemitted light from the light emitter to the interior of therepositionable knob.
 13. The knob assembly of claim 12 wherein the atleast one light source is located on the rear side of the PCB and thelight guide directs the light from the rear side to the interior of therepositionable knob.
 14. The knob assembly of claim 13 wherein therepositionable knob further comprises a rotatable shaft having one endfixedly mounted to the structural framework and another end rotatablymounted to the PCB.
 15. The knob assembly of claim 14 wherein the atleast one light source comprises multiple light sources positionedaround the rotatable shaft.
 16. The knob assembly of claim 15 whereinthe position sensor comprises a rotary encoder having a body defining aninterior, a rotatable shaft rotatably supported by the body, wherein therepositionable knob is fixedly mounted to the rotatable shaft to effectrepositioning of the repositionable knob by rotation of the rotatableshaft.
 17. The knob assembly of claim 16 wherein the body comprisesmultiple windows corresponding to at least one of the multiple lightsources through which light emitted from the at least one of themultiple light sources is transmitted to the interior, and multiplelight guides corresponding to the multiple windows and opticallycoupling the body interior to the repositionable knob interior, whereinlight emitted from the at least one of the multiple light sources passesthrough the corresponding window and is transmitted by the correspondinglight guide from the body interior to the repositionable knob interior.18. The knob assembly of claim 17 wherein the windows and correspondingmultiple light sources are spaced around the body.
 19. A knob assembly,comprising: a repositionable knob having an outer surface and an innersurface defining an interior and a light-transmissive indicia providedon the repositionable knob and viewable from the outer surface; at leastone light source located relative to the repositionable knob andemitting light to transmit light into the interior of the repositionableknob and backlight the light-transmissive indicia; a position sensorproviding a position output indicative of a position of therepositionable knob; and a controller receiving the position output andoperably coupled to the at least one light source to independentlycontrol an intensity of light transmitted by the at least one lightsource, the controller programmed to use the position output to controlthe intensity of the at least one light source to maintain apredetermined backlighting of the light-transmissive indicia.
 20. A knobassembly, comprising: a repositionable knob having an outer surface andan inner surface defining an interior, a structural framework locatedwithin the interior, and a light-transmissive indicia provided on therepositionable knob and viewable from the outer surface; at least onelight source located relative to the repositionable knob and emittinglight into the interior of the repositionable knob past the structuralframework and backlight the light-transmissive indicia; a positionsensor providing a position output indicative of a position of therepositionable knob; and a controller receiving the position output andoperably coupled to the at least one light source to independentlycontrol an intensity of light transmitted by the at least one lightsource based on the received position output to maintain a predeterminedbacklighting of the light-transmissive indicia.